- Anatomy:
-
origin:
- long head: supraglenoid tuberosity of the scapula
- short head: apex of coracoid process of scapula;
-
synergists: brachialis,
brachioradialis,
supinator;
-
innervation: musculocutaneous,
C5 >
C6;
-
insertion: bicipital tuberosity of the radius and lacertus fibrosis;
- references:
-
The anatomy of the bicipital tuberosity and distal biceps tendon.
-
Distal Biceps Tendon Anatomy: A Cadaveric Study.
-
action:
- flexes and supinates the forearm at the elbow;
- reversed origin insertion action: both hands of biceps brachi are active during flexion of arm at shoulder joint, with the long head being more active;
-
long head of biceps:
- attaches to the supraglenoid tubercle of glenoid & has stabilizing and depressing action on humeral head;
- it can act as a tether and block closed reductions of proximal humerus;
- it is a useful landmark from which the rotator interval can be identified so that bone fragments are properly identified & rotator cuff are preserved;
- references:
-
The role of the long head of the biceps brachii in superior stability of the glenohumeral joint.
-
The Transverse Humeral Ligament. A Separate Anatomical Structure or a Continuation of the Osseous Attachment of the Rotator Cuff?
- Subluxations and dislocations of the tendon of the long head of the biceps. J Shoulder Elbow Surg 1998;7:100-108.
- Pathologic Conditions:
-
biceps tendonitis :
-
distal biceps tendon rupture:
-
proximal biceps tendon rupture:
-
erb's palsy :
- persistent absence of
biceps muscle function at age 6 months in pts w/
C5-6
brachial plexus palsy from birth has been shown to
correlate w/ a poor prognosis for functional recovery;
- early
brachial plexus exploration & nerve grafting will improve f(x);
Traumatic closed transection of the biceps brachi in the military parachutist.
Rupture through the short head of the biceps muscle belly. A case report.
A technique for maximizing biceps recovery in brachial plexus reconstruction.
